Detonator safety device



Feb. 14, 1933. J. T. c. WILLIAMS ET AL 1,897,585

DETONATOR SAFETY DEVICE Filed July 12 1932 INVENTORS ATTO R N EY CITPatented Feb. 14, 1933 JOSEPH T. C. WILLIAMS AND RUSSELL J. TOWNSEND, OFARCADIA, PENNSYLVANIA DETONATOR SAFETY DEVICE Application filed July 12,

This invention relates to safety devices for electric detonators and itsgeneral ob- ]ect is to provide a detachable clip for normally connectingthe exposed portions of the from the. detonator after the latter hasbeen set, and this function is accomplished by merely pulling upon thelead wires at a place of safety, or adjacent to the source of electricenergy used for exploding the detonator.

Another object of the invention is to provide a safety device of thecharacter set forth, that is simple in construction, inexpensive tomanufacture, provides for the greatest possible safety, and is extremelyefficient in operation and service.

This invention also consists in certain other features of constructionand in the combination and arrangement of the several parts, to behereinafter fully described, illustrated in the accompanying drawing andspecifically pointed out in the appended claims.

Indescribing our invention in detail, reference will be had to theaccompanying drawing wherein like characters denote like orcorresponding parts throughout the several views, and in which:

Figure l is a side elevation illustrating our device in use.

Figure 2 is a top plan view of Figure 1.

Figure 3 is an enlarged fragmentary view illustrating the clip forconnecting the wires together.

5 cured thereto lead wires which are insulated 1932. Serial No. 622,166.

but have exposed free ends to be arranged in circuit with a source ofelectric energy or connected to the latter. Due to the fact that thefree ends are exposed or in other words have the insulation removedtherefrom, these ends may accidentally come in contact with an electriccircuit, and thereby result in exploding the detonator prematurely. Byusing our device, such a casualty could not possibly happen as the leadwires are electrically connected together and in the event the exposedends of the wires should accidentally come in Contact with an electriccircuit, the current could not pass to the detonator, regardless of thestrength of the current, and if the current is of great strength, theportions of the wire that are connected together may fuse and burn off,thereby. completely disconnecting the detonator.

The lead Wires in the present instance are indicated by the referencenumerals l and 2 and are insulated in the usual manner, as well as haveone of their ends exposed for connection with the source of electricalenergy B. The wires also have their insulation removed at parallelplaces adjacent to their connection with the detonator as clearly shownin Figures 1 and 2, and these exposed portions which are indicated bythe reference numerals 3 and 4 are adapted to have secured thereto aclip 5 formed from suitable conductive material so that electric currentwill pass from one wire to the other, for the purpose of setting up ashort circuit in the event that the exposed ends of the wires shouldcome in contact with an electric circuit.

The clip 5 is formed from a single piece of material and has one endportion 6 bent at right angles to its body and this end portion isprovided with an opening 7 for a purpose which will be later-described.

One of the exposed portions may he spot welded or permanently fixed t0the body of the clip 5 and for distinction, we have shown the exposedportion 3 secured accordingly as at 8 to the body, while the exposedportion- 4 is lightly solderedas at 9. I

The lead wires are not only provided with suitable insulation, but areprovided with a casing for holding them associated, and con-' Qthe wiresin any suitable manner but it is preferred that the wires be knottedtogether as at 11, with the flexible element secured to the knot. Theflexible element is relatively short and has secured to its opposite enda hook 12 which is adapted to be received in the opening 7 In view ofthe fact that the flexible element is short, it will be apparent that inorder to secure the hook 12 in the opening 7 that it is necessary thatthe lead wires be looped upon themselves as at13. While we haveillustrated one of the lead wires permanently fixed to the clip 5 andthe other lead wire temporarily connected thereto, both of the wires maybe permanently fixed thereto, and in that event the clip will be madefrom soft material that can be easily torn and is split longitudinallyfor a major portion of its length.

From the above description and disclosure of the drawings, it will .beobvious that we liaveprovided a safety device to prevent detonators andsimilar explosives from exploding prematurely, and in theuse of thedevice as shown, the explosive is arranged in the position desired andthe hook is placed in the opening 7. The operator then grasps the leadwires'at a safe distance or at a point adjacent to the source ofelectric energy B and pulls upon the wires which will result in the clipbeing disconnected from the exposed portion 4 so that a circuit can becompleted to the detonator. The exposed ends of the wires can then beconnected to the source 13 to close the circuit from the source to thedetonator.

It is thought from the foregoing description that the advantages andnovel features of our invention will be readily apparent.

lVe desire it to be understood that we may make changes in theconstruction and in the combination and arrangement of the severalparts, provided that such changes fall within the scope of the appendedclaims.

What we claim is:

1. In a safety device for an electric detonator, a pair of insulatedlead wires electrically connected to the detonator and having parallelexposed portions arranged adjacent to the detonator, a clip electricallyand detachably connecting the exposed portions together to shunt acircuit to the detonator, flexible means adapted to be secured to thelead wires and to said clip respectively whereby upon pulling upon thelead wires at a safe distance from the detonator, the exposed portionsare disconnected so that a circuit can be completed to the detonator.

, 2. In a safety device for an electric detonator, a pair of insulatedlead wires adapt- Vtor. V

3. In a safety device for an electric deto- 7 circuit to the detonatorand being provided i with an opening, a flexible element having one endconnected to the lead wires, a hook secured to the opposite end of saidflexible element and being adapted to be received in said opening, saidflexible element being relatively short to provide a loop in the leadwires when the hook is arranged in the opening whereby upon pulling onthe lead wires the exposed portions will be disconnected so that acircuit can be completed to the detonanator, a pair of insulated leadwires adapted to have one of their ends electrically connected to thedetonator and being provided with exposed portions arranged inparallelism with respect to each other and adjacent to the detonator, aclip of conductive material having one of the exposed portionspermanently fixed thereto and theother exposed portion detachablyconnected thereto, to temporarily shunt a circuit to the detonator, andmeans. having one end secured. to the lead Wires and its opposite endsecured to the clip whereby upon pulling on the lead wires thedetachably connected exposed portion will be removed from the clip sothat a circuit can be completed to the detonator.

4. In a safetydevice for an electric deto-.

nator,'a pair of insulated lea-d wires adapted to be electricallyconnected to the detonator and having parallel exposed portions, meansfor electrically connecting the exposed portions together to shunt acircuit to the detonator, a flexible element having one end secured tothe lead wires and its opposite end secured to said means, said flexibleelement being relatively short to provide a loop in said leadwires-between the connection of the flexible element thereto and theexposed portions, whereby upon pulling on the lead wires, the said meanswill be arranged to disconnect the exposed portions so that a circuitcan be completed to the detonaton,

In testimony whereof we aflix our signatures.

JOSEPH T. C. WILLIAMS. RUSSELL J. TOWNSEND;

